iPhone 4S dropping network and data at random

2 weeks with my new replaced iPhone 4s and ive had only 1 dropped call which was probably due to the weather.

I really think is a hardware problem afterall. If you can replace it, i truly advise you to do so.

I was facing a similar problem with my iPhone 4s. Lot of network call drops and really bad Battery Life. I tried everything including restore, upgrade to iOS 5.01 (9a406) and lot else suggested on the different forums.

Finally what has worked is a switch of network provider. I use it in India and had Airtel. However I tried a new SIM card from Vodafone which worked well and I had excellent battery life as well as zero call drops. Now I am porting my original number over to Vodafone.

Even Apple Customer Support suggested I exchange my Phone but the guys here did not have my model in stock.

So while waiting I figured out the problem.

First I switched the Automatic network selection to OFF in Settings->Carrier.

Secong I selected a different carrier and forced the phone to stick to it. That improved both battery life and call drops.

Third I got a different SIM from the carrier I had tried (Vodafone in my case) and tried it for 5 days. I got battery life pretty much as claimed by Apple. 8-9 hours of usage time with WiFi on and over 2 days on standby.

This confirmed to me that it was not a hardware issue but rather some sort of Carrier/SIM issue.

You can try it and see if it helps.

It's a hardware issue which they are aware. I replaced my iPhone without any problems in Germany in Munich Apple store I got myself a new one from D3 Factory China and for know everything works, I just got e-mail from apple store Munich and they put the description problem: Sim can not be recognized

so they know what is the issue.

Thanks all hope to solve your problems with iPhone too.

CHeers

BYe

Here is a simple guide on how to fix the iPhone 4s signal problem that has plagued so many people. Hopefully this can help some of you.

@markymark8

The advice you're linking to works for a tiny subset of all people suffering this problem.

There seem to be only two high-success-rate solutions at this stage:

1. Replace the phone (ideally with one running 5.0)

2. Install 5.1b3

Of course, there may be lots of different problems which are resolved by some solutions and not by others.

The problem looks like some sort of interaction between SIM and carriers. For some people, changing SIM has worked, and for some people changing carrier has worked. What is definitely true is that there is a serious problem with the 4S and Apple is not coming clean about it ...

While I'm writing, can I remind peoople that the SIM-tray tape solution is complete nonsense. The SIM tray is coated with an insulated film, and using tape may damage this and create new problems.

EDIT: Also while I'm writing, many people have asked why this got worse between 5.0 and 5.0.1 ... well the answer seems to be that the unlocking community has been playing with things like the Gevey unlocker (look it up, it's clever in some ways, but stupid in others). This means that Apple has necessarily become stricter and stricter about how the phone commuicates with the SIM. I'm certain Apple's attempts to stay ahead of unlockers are hurting all of us.

Update

7th day with the new iPhone 4S

Drops: 0

SIM Cards Problems: 0

Lost Connections: 0

Firmware: 9A406

Conclusion: Hardware Issue (at least for me).

Having the same model with the "problematic" firmware that caused problems with my old phone just leads me to think that... Hardware Issue.

@Wibbly le Mönde: Very interesting post

Regards from Chile

Hi

M from India and got a new factory unlocked iPhone 4s 16 gb white from some of the apple store few days back in India

I m continuously facing signal and battery problem with the phone, tried almost every thing whichever was on the apple support community and unfortunately i was not able to fix it. Finally i called up costumer care India and tried all that which they told me to do buti was thr where i started so finally i took my device to apple service center and addressed the issue ... they diagnosed and returned the handset back to me after 2 days i was happy to collect it and was very excited to put my sim in it, after inserting the found full signal bars so it was the lifetime moment for me !! after using it for 2 to 3 hours i faced the same problem ?? Again i took my phone to apple service finally they replaced it with a new device (as a policy)problem continued after a day i got it. now i have discussed it with the apple service and they say to deactivate 3g or data service on my phone and this shud possibly solve the problem i asked them that i have paid 900 $ approx for this phone and u want me to use it only for calling and dialing, i would have taken some low budget phone in that case .... why i have splurged so much of money just to avail the facility which is coming with 4s, service guy was out of answer....uhhh

can somebody tell me the solution for it.... if there is no solution then apple should put an advertisement on news paper and stick posters at there istores saying "if u wish to use 3g or data on ur phone then pls buy it at ur own risk" because we are not able to fix any signal and battery related problem at least in India.

i am really surprised that the every 5th phone which is factory unlocked persists the same problem in India while phone coming through Airtel and Aircel are absolutely working fine why ???? but Apple don't even have any answer to it. It seems really funny that one spent huge money just to receive and dial the calls. Mr.Cook are u listening ????? why did u guys launched this phone so early without testing it to death. I can feel the the difference between two Mr. Cook and Jobs. Jobs never had launched it if there were so much of problem with the phone. Apple i want a permanent solution to it or return my money

people pls help me to solve the issue.

iam from the philippines i have the same problem with my 4s signal have 2 bars then it will jump to full bar then down again. i have already tried resetting, swithing the pin off, turning off the automaic network setting, changing the sim, but to no avail still have the same problem. i would also like to note that i am experiencing this while in the smart network but it i switch to globe the problem gone. but unfortunately i need to be in the smart network. can anyone suggest a cure?

Hi,

I am also from the Philippines with a locked iphone 4s only last December. No issues on the first 3 week even while on roaming. first encounter with the issue was 4 weeks ago when i was back in Manila and eversince the "invalid sim" every morning and the "searching" to "no service" more than 5x a day. Tried all the "solutions" offered in this thread several times, changed microsim from Globe already but still the issue is there. I am now again outside the Philippines and is using my iphone as an ipod as i always have the "no service" error throughout the day.

I visited a MAC Service Center here in TH but was informed that they only service those products procured via the net and was asked to visit the carrier which i did (went to the carrier partner of Globe) and was advised that it is with the microsim/carrier back home (Globe) as they tried to insert the sim in an iphone and encountered the same issue.

Hoping that IOS5.1 really solved the issue as per the feedback from those who installed the beta version and still i can use the same sim i have right now as i am on a postpaid plan and cannot get a new sim card from Globe just in case.

Any other solution prior to the ios 5.1 release?

I think globe will replace your sim card if it is malfunctioning as your a postpaid subscriber, if after the replacement you still encounter the same problem then insist that your unit be replaced.

Hi,

Am from India..Facing a similar problem...Have a 4s with a Vodafone sim...Had this problem of ' No Sim' every morning and "no service" at least 8-10 times a day...upgaded to 5.0.1 in early Dec'11...Worked great for me for 2 months...no problems whatsoever..was really a very satisfied customer until these problems surfaced again 10 days ago...network once again keeps dropping 8-10 times a day and facing the problem of 'No Sim' every morning...incomming calls not getting thru...everytime I make an outgoing call it goes into 'searching' mode...and have to wait a couple of min before trying again...checked my sim on my old mobile...sim worked fine...swapped it with an Airtel sim and checked it for a day...same problems...

This is a fantastic piece of engineering and art...messed up by some bad software...searching for a solution.

so has anyone tried fixing this problem with 5.1 update?

Hi everyone

I've updated yesterday my iPhone 4S to 5.1. I still have the "No Service" issue.................

It seems to be a hardware problem

i can see that now is possible to turn off 3g (settings- general- network- 3g off)

try this, and maybe you should try disabling SIM pin request (settings- phone- SIM PIN- off)

Hi

Updated to 5.1 this morning .... So far so good.. 8hrs now...all calls goin thu in the fist attempt...getting incoming calls too... Cheked in low signal areas also...it is able to latch on the signal with out any problems ....keeping fingers crossed ... Should not get invalid sim tomorrow morning.